docs: def setDigitalMaximum(self, edfsignal, digital_maximum):
          """
          Sets the samplefrequency of signal edfsignal.
          Usually, the value 32767 is used for EDF+ and 8388607 for BDF+.
  
          Parameters
          ----------
          edfsignal : int
              signal number
          digital_maximum : int
              Sets the maximum digital value
  
          Notes
          -----
          This function is optional and can be called only after opening a file in writemode and before the first sample write action.
          """
          if (edfsignal < 0 or edfsignal > self.n_channels):
              raise ChannelDoesNotExist(edfsignal)
          self.channels[edfsignal]['digital_max'] = digital_maximum
          self.update_header()